Cardiac valve prostheses can essentially be divided into two basic categories, namely “mechanical” valve prostheses, in which the blood flow through the valve is controlled by one or more obturators constituted by rigid bodies mounted so as to be able to oscillate or tilt in a rigid support, and “biological” valve prostheses, in which blood flow is controlled by valve leaflets formed of biological tissue. The biological valve leaflet material, which is subject to treatment (stabilization) to render it biologically inert, can be derived from a natural cardiac valve taken from an animal (for example a pig) or can be formed from biological tissue other than valve tissue (for example, bovine pericardium). Biological valve prostheses may in turn take the form of “stented” valves, where the valve leaflets are mounted on a rigid or slightly flexible stent or armature, and “unstented,” or “stentless,” valves.
EP-A-0 515 324 and U.S. Pat. No. 5,713,953 disclose various embodiments of stentless cardiac valve prostheses, including embodiments where the biological material is replaced (either partially or completely) with an artificial/synthetic material such as a micro-porous and/or composite synthetic material, for example polyurethane. Stentless valve prostheses may exhibit as a whole characteristics of deformability that offer functional advantages due to a great similarity to the anatomy of natural valves. On the other hand, because stentless valves do no maintain a consistent shape, they may be somewhat more challenging to implant properly. Optimal implantation of a stentless valve, either by conventional or minimally-invasive surgical techniques, may involve positioning the prosthesis at the implantation site (e.g., an aortic site) using a holder device. Such a holder may support the prosthesis during production, packaging and/or implantation of the prosthesis by the surgeon. Holder devices may include a support or “grip” hub adapted for connection to a manipulation handle. The surgeon can thus locate a prosthesis (held by the holder) at the implantation site and properly orient it with respect to the native valve anatomy.
One such exemplary holder is shown in US 2008/0262603 A1, which includes a grip element and a plurality of arms for supporting a prosthetic heart valve at an intermediate position between the commissures. The holders shown in the prior art however are either quite complex in construction or design. Additionally, the manipulation capabilities of these holders may often be not completely satisfactory.